| Abstract: | The type III carbonaceous chondrites Kainsaz and Efremovka have been analysed for eighteen major, minor and trace elements by X-ray fluorescence spectrometry. A comparison of the data on Kainsaz with four other Ornans sub-type carbonaceous chondrites reveals a remarkable degree of constancy of composition. Efremovka, together with Leoville and Coolidge, may be distinguished from the other Vigarano sub-type carbonaceous chondrites by their lower Na and K contents, variable Na/K ratios and relatively low Ca/Al ratios. Some observations are made on the ratio Na/K in various types of stony meteorite; the magnitude of the ratio in the basaltic achondrites appears to be more similar to that in the carbonaceous chondrites than in the ordinary chondrites. |
